/* 页面整体样式 */
body {
    font-family: Arial, sans-serif;
    background-color: #f4f4f4;
    color: #333;
}

header {
    background-color: #333;
    color: #fff;
    padding: 10px 20px;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

header .logo {
    font-size: 24px;
}

header .user-options a {
    margin-left: 15px;
    color: #fff;
    text-decoration: none;
}
nav {
    background-color: #222;
    color: #fff;
    padding: 10px 20px;
}

nav ul {
    list-style: none;
    display: flex;
    justify-content: space-around;
}

nav ul li {
    display: inline;
    margin-right: 20px;
}

nav ul li a {
    color: white;
    text-decoration: none;
}

/* Tutorial Introduction */
.tutorial-intro {
    text-align: center;
    padding: 40px;
    background-color: #fff;
    margin: 20px;
    border-radius: 10px;
}

.tutorial-intro h1 {
    font-size: 32px;
}

.tutorial-intro p {
    font-size: 18px;
}

/* Tutorial Selection */
.tutorial-selection {
    text-align: center;
    padding: 40px;
    background-color: #fff;
    margin: 20px;
    border-radius: 10px;
}

.tutorial-selection h2 {
    font-size: 28px;
    margin-bottom: 20px;
}

.tutorial-cards {
    display: flex;
    justify-content: space-around;
    flex-wrap: wrap;
}

.tutorial-card {
    background-color: #f9f9f9;
    padding: 20px;
    border-radius: 10px;
    width: 250px;
    margin: 10px;
    text-align: center;
    box-shadow: 0 4px 8px rgba(0, 0, 0, 0.1);
}

.tutorial-card h3 {
    font-size: 24px;
    margin-top: 15px;
}

.tutorial-card p {
    font-size: 16px;
    margin: 10px 0;
}

.tutorial-card .tutorial-link {
    display: inline-block;
    background-color: #007BFF;
    color: white;
    padding: 10px 20px;
    border-radius: 5px;
    text-decoration: none;
    margin-top: 15px;
}

.tutorial-card .tutorial-link:hover {
    background-color: #0056b3;
}

.tutorial-card img {
    width: 100%;
    height: auto;
    border-radius: 8px;
}

/* Footer */
footer {
    text-align: center;
    background-color: #333;
    color: white;
    padding: 20px;
    margin-top: 40px;
}
